Objective. To explore the influence of M2-polarized tumor-associated macrophages (TAMs) on high-risk human papillomavirus (hr-HPV)-related cervical carcinogenesis and metastasis.Methods. CD68+ and CD163+ macrophages were examined immunohistochemically in a series of 130 samples, including 26 cases of normal cervical tissues, 59 cases of cervical intraepithelial neoplasia (CIN), and 45 cases of squamous cell carcinoma (SCC), and the results were statistically analyzed. The macrophage count was corrected for the epithelial and stromal compartments respectively. Clinical data were also obtained.Results. High counts of CD68+ and CD163+ macrophages were associated with hr-HPV infection (both p < 0.05) and positively correlated with cervical carcinogenesis (Spearman's rho = 0.478, p = 0.000; Spearman's rho = 0.676, p =0.000, respectively). The immunostaining pattern of CD163 exhibited clearer background than that of CD68. CD163+ macrophages showed a more obviously increasing migration into the epithelium along with the progression of CIN to invasive cancer. Notably, a high index of CD163+ macrophages was significantly associated with higher FIGO stages (p = 0.009) and lymph node metastasis (p = 0.012), but a similar finding was not found for CD68+ macrophages (p = 0.067, p = 0.079, respectively).Conclusions. Our study supported a critical role of TAMs as a prospective predictor for hr-HPV-related cervical carcinogenesis. CD163, as a promising TAMs marker, is superior to CD68 for predicting the malignant transformation and metastatic potential of cervical cancer.

MicroRNAs have implicated in the relapse and metastasis of cervical cancer, which is the leading cause of cervical cancer-related mortality. However, the underlying molecular mechanisms need further elucidation. Our present study revealed that miR-221-3p is transcriptionally promoted in metastatic cervical cancer tissues compared with non-metastatic cervical cancer tissues. Forced overexpression of miR-221-3p facilitated EMT and promoted cell migration and invasion in vitro and lymphatic metastasis in vivo. Twist homolog 2 (TWIST2) was found to be a key transcription factor binding to the promoter of miR-221-3p. Inhibitors of miR-221-3p drastically reduced the induction of EMT and decreased cell migration and invasion mediated by TWIST2. By combined computational and experimental approaches, THBS2 was recognized to be an important downstream target gene of miR-221-3p. In cervical cancer tissues, especially with lymphatic metastasis, miR-221-3p and TWIST2 were increased and THBS2 was decreased, suggesting that TWIST2 induces miR-221-3p expression and consequently suppresses its direct target THBS2 in lymphatic metastasis CC. Our findings uncover a mechanistic role for miR-221-3p in lymph node metastasis, suggesting that miR-221-3p is upregulated by the transcription factor TWIST2 and downregulates its target THBS2, which may potentially promote lymph node metastasis in cervical cancer.

Tumor metastasis remains a major obstacle for improving overall cancer survival in cervical cancer (CC), which may be due to the existence of tumor microenvironment-related cancer stem cells (CSCs) and epithelial-mesenchymal transition (EMT). The mechanism underlying these processes needs to be further elucidated. Here, we report that TGF-β1, one of the key microenvironmental stimuli, can enhance CSC characteristics, facilitate the EMT, and induce CK17. Silencing CK17 expression attenuated CSC-like properties without affecting the EMT markers induced by TGF-β1, whereas forced overexpression of CK17 promoted lymphatic metastasis in vivo even without EMT inducement. Inhibitors of ERK1/2 signaling drastically decreased the induction of CK17 mediated by TGF-β1. By combined computational and experimental approaches, we identified and validated that MZF1 was a key transcription factor binding to the promoter of CK17. Taken together, these results demonstrate that CK17 induced by the TGF-β1-ERK1/2-MZF1 signaling pathway facilitates metastasis by promoting the acquisition of CSC properties rather than by inducing the EMT process in CC, suggesting that this CK17-related signaling pathway might be a suitable target for the development of therapy for CC metastasis.

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